1. Field of the Invention
The present invention relates to a method of producing a sealing strip and similar profiled strips of rubber and rubber-like elastomers. An overlay strip of one material is disposed on and is bonded to, a portion of the outer, cross-sectional periphery of a main strip of a second, different material, with the overlay strip extending over the entire length of the main strip. The present invention also relates to a novel construction of the extrusion press that is suitable for carrying out such a method.
2. Description of the Prior Art
Various sealing strips are required for bordering doors or windows of motor vehicles or in buildings. On the one hand, due their elastic deformability, these strips provide good seals against the penetration of moisture and air. However, on the other hand, due to the rubber-like base material, these strips provide too much friction relative to the windowpanes or door surfaces that rest against or on the strips, and are movable relative thereto. It is known, for such applications, to provide portions of the sealing strips with a friction-reducing covering. The same conditions exist when differently colored or differently structured strips are to be applied to the profile, for example for aesthetic reasons.
In all cases, it is desired to cover the outer surface of the sealing strip with a relatively thin covering of a material other than rubber.
Up to now, such covers were generally applied to the finished base strip at a later time, and were frequently applied manually. This cover could be applied, for example, by electrostatic flocking, lacquering, or gluing.
In contrast, an object of the present invention is to continuously produce, in a ready-to-use state, profiled strands, especially those that are used as sealing strips, in a single operation while avoiding any manual operation, with said profiled strands thereby having an overlay strip that is satisfactorily bonded to the base main strip.